#include <bits/stdc++.h>
#define name "way"
#define FOR(i, a, b) for (int i = a; i <= b; ++i)
#define FORD(i, a, b) for (int i = a; i >= b; --i)
#define ll long long
#define fi first
#define se second
#define ii pair <int, int>
#define sz(a) (int) a.size()
#define pb push_back
#define MASK(x) (1ll << x)
#define bit(x, i) ((x >> i) & 1)
#define pop_count(x) __builtin_popcount(x)
#define mingdu signed main()
using namespace std;
const ll mod = 1e9 + 7;
void add(ll& a, ll b) {
a += b;
if (a >= mod) a -= mod;
if (a < 0) a += mod;
}
template<class X, class Y> void mx(X &x, const Y y) {if (y > x) x = y;}
template<class X, class Y> void mn(X &x, const Y y) {if (y < x) x = y;}
const int N = 1e5 + 5;
int a[N], n, m, tin[N], low[N], timer;
int scc[N], cnt;
char ans[N];
ll diff[N];
bool d[N], vis[N];
vector <ii> adj[N], g[N];
ii edge[N];
void nhap() {
cin >> n >> m;
FOR(i, 1, m) {
int u, v; cin >> u >> v;
adj[u].pb({v, i});
adj[v].pb({u, i});
edge[i] = {u, v};
}
}
void dfs(int u, int p) {
tin[u] = low[u] = ++timer;
FOR(i, 0, sz(adj[u]) - 1) {
int v = adj[u][i].fi;
int id = adj[u][i].se;
if (id == p) continue;
if (!tin[v]) {
dfs(v, id);
low[u] = min(low[u], low[v]);
if (low[v] > tin[u]) d[id] = 1;
}
else low[u] = min(low[u], tin[v]);
}
}
void dfs_scc(int u) {
scc[u] = cnt;
FOR(i, 0, sz(adj[u]) - 1) {
int v = adj[u][i].fi;
int id = adj[u][i].se;
if (!d[id] && !scc[v]) dfs_scc(v);
}
}
ll DFS(int u, int p) {
ll s = diff[u];
vis[u] = 1;
FOR(i, 0, sz(g[u]) - 1) {
int v = g[u][i].fi,
id = g[u][i].se;
if (v == p) continue;
ll t = DFS(v, u);
int x = edge[id].fi, y = edge[id].se;
x = scc[x], y = scc[y];
if (t > 0) ans[id] = (x == v && y == u) ? 'R' : 'L';
else if (t < 0) ans[id] = (x == u && y == v) ? 'R' : 'L';
s += t;
}
return s;
}
void giai() {
FOR(i, 1, n) if (!tin[i]) dfs(i, -1);
FOR(i, 1, n) if (!scc[i]) ++cnt, dfs_scc(i);
FOR(i, 1, m) if (d[i]) {
int u = edge[i].fi, v = edge[i].se;
int x = scc[u], y = scc[v];
g[x].pb({y, i});
g[y].pb({x, i});
}
int q; cin >> q;
while (q--) {
int x, y; cin >> x >> y;
int u = scc[x], v = scc[y];
if (u == v) continue;
diff[u]++;
diff[v]--;
}
FOR(i, 1, m) ans[i] = 'B';
FOR(i, 1, cnt) if (!vis[i]) DFS(i, 0);
FOR(i, 1, m) cout << ans[i];
}
mingdu {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
if (fopen(name".inp", "r")) {
freopen(name".inp", "r", stdin);
freopen(name".out", "w", stdout);
}
nhap();
giai();
return 0;
}
